hello all,

I am interested in trying the blurry clouds effect. I have just one question, though.
Do you take multiple short exposures (or combine single short exposures) or you do a single long exposure?

thanks a lot

Daniel

A single long exposure usually works depending on the cloud speed. Similar to the milky water effect where exposures of 1/2 second to minutes can work.

JP

thanks, john
dp

do you have an example of the effect that you want?

mal

hi Mal,

not sure it this is the right way to post links here, but:

http://1x.com/v2/#photos/architecture/24919/

without asking that artist what the set up was, it would be my guess that he used an infra red filter, possibly the hoya r72 with an unconverted ir camera. It has rendered the foliage of the trees slightly pale or white in tone, very typical of that filter but has also given the ND qualities that the filter gives to allow the extended exposure time. The r72 add 18 stops to any given exposure time, sometimes leading to exposure times of over 2 mins even in brightly lit conditions.

mal

thanks a lot. i have some ND filters to try out, not IR.
Now I just need clouds...;)
thanks a lot for your time, Mal
dp

Wow, that shot is spectacular. There's always something to learn!

The exposure should not be longer than 3 seconds. If the effect will not come you can use PS as you select the sky and apply motion blur as strong as you wish:-) Mostly this has applied by architecture pictures but also for landscape it will work.

Blurry clouds? Given: clouds. A must have. Next: wind. The more wind the less exposure time and the less extreme ND needed, however the best effects are achieved with an 8-stop filter (B+W and others), a 9-stop (Hoya x400 and others) or the 10 stop B+W. But, either get the sun well hidden behind those clouds or out of frame or else you'll just blow out the exposure. Combine with water, eg ocean, over several minutes and you've got it.

Daniel,

My opinion is that you need to try to do this in 1 exposure. I've tried blending these, and they don't look terribly good. You will want a LOT of ND as mentioned above. Here's the thing though, much of it depends on the altitude of the clouds and their speed. Low, fast clouds will give you the effect much more quickly than high, slow ones. Also, if you are shooting towards the horizon, they will take longer to blur than if you are shooting almost straight up.

A quick tip to getting the right exposure so you aren't sitting there for 10 minutes and figuring out that it was wrong: Crank you ISO up a bunch and take a test shot at your selected aperture. Example, if I shoot an image at ISO 6400 at f16 and it is exposed correctly in 15 seconds, then you can expect the same exposure at ISO 100 in 16 minutes, remembering that if it is getting darker as its exposing you will want to add a little time for that. That should get you started out on the right track.

On these exposures, they always seem to take longer than you think... you will be looking at many minutes to have it really work in most cases.